The extremely frou-frou affair does not welcome smokers, vapers, and everyone in between into its hallowed halls, and now it's being reported that several museum donors are FURIOUS that some celebs were puffing up a storm in the museum's bathrooms.

"As a donor to the Met, I was so insulted to see all these ‘celebrities' smoking and taking selfies of themselves in the bathroom. Mostly, it's disrespectful to the art collection which needs to be kept 100 percent smoke-free. I would honestly like to see these people fined by the city."

TMZ reports the 24-year-old stunner just filed court docs requesting the left-handed 1959 Martin D-18E acoustic guitar be handed over to an art shipping company until it's decided who gets it.

Silva argues Miz Cobain gave him the famous instrument as a wedding present… something the model adamantly denies, saying there's no way in hell she'd give him such a "priceless family heirloom."

Not to mention the fact Isaiah, who leads the band The Eeries, plays guitar RIGHT HANDED! He couldn't even use the bridge-flipped custom!

In the legal docs, Frances asks the court to allow her to inspect the condition of the guitar before storing it away with a third party until the divorce is settled. Sounds like a reasonable request to us!

We'll keep you updated as we learn the judge's decision. Whose side R U on??

As we reported, Frances Bean Cobain's ex husband Isaiah Silva is requesting no less than $25K a month in spousal support, claiming Courtney Love's daughter has $100 million of her dad's money. The couple — who did NOT have a prenup — split in March, after being married for less than two years.